Soybean is one of the most important commercial crops world-wide. The ability to evaluate genetic elements along with nucleotide sequences of interest is important to the development of soybean plants with improved agronomic traits. However, evaluation and testing of genetic elements in stably transformed soybean plants is time and resource intensive. In contrast, evaluation of genetic elements using transient expression systems can be done in several days for far less cost.
Several viral based in-planta transient systems have been reported for soybean (Zhang and Ghabrial, Virology 344:401-11 (2006); Wang et al., MPMI 19:304-312 (2006); Zhang et al., MPMI 22:123-131 (2009); Zhang et al., Plant Physiol. 153:52-65 (2010); Yamagishi and Yoshikawa, Plant Mol Biol. 71:15-24 (2009). While viral-based transient transformation systems are useful for systemic and high level expression of nucleotide sequences of interest, viral-based transient transformation systems are less useful for evaluating genetic elements such as enhancers, promoters, whole expression cassettes, viral genes, and any genetic element that is larger than 2-3 kb. Expression of multiple genes/traits is commonly desired. Such constructs can be quite large, (e.g., 5-25 kb) and generally cannot be tested in plants using known viral systems.
Accordingly, the present invention addresses previous shortcomings in the art by providing compositions and methods for transiently expressing a nucleotide sequence in a soybean plant using binary vectors.